Download Exploring Regions of the United States Section 1

Exploring Regions of the United States
Section 1 - Introduction
Because Earth is so large, geographers divide it into regions to study. A region is
an area with common features
that set it apart from other
areas. In this book, we have
divided the United States into
five regions to study.
In this chapter, you will learn how
geographers study regions. One
way is by using
maps. Geographers use maps to help them think about five topics, or themes, of
geography. These are the five themes of geography:
Location: Where is this place located? What is it near?
Place: What is this place like?
Human-environmental interaction: How does this place affect the people living
here? How do the people who live here affect this place?
Movement: How do people, goods, and ideas move to and away from this place?
Regions: What features about this place set it apart from other places?
Try answering the questions above about a place you know well—your school. Now
you are thinking like a geographer. Keep thinking that way as you read more about
the regions of the United States.
Section 2 - Location and Direction
Every place has its own location. A location is the site
where something can be found. People describe locations
in many ways. You might describe the location of your
home by talking about what it is near. This is the relative
location of your home. Or you might use your street
address. This is the exact location of your home.
Geographers use globes and maps to show the locations of places on Earth. Globes
are round like Earth. They are useful when you want to know where places are on
the planet. When you need to see where many places are all at once, maps can be
more useful. Maps show all or
part of Earth on a flat surface.
To use a map, you need to know
the four cardinal
directions. North is the direction toward the North Pole. When you face north,
your back is facing south. East is to your right. West is to your left. On a map, the
letters N, S, E, and W stand for the cardinal directions.
The intermediate directions are halfway between the cardinal
directions. Northeast, for example, lies halfway between north and east. The other
intermediate directions are southeast, southwest, and northwest. On a map, the
letters NE, SE, SW, and NW stand for the intermediate directions.
Most maps use a compass rose to show directions. It sits on each map with N
pointing toward the North Pole. This tells you which way is north.
Exploring Regions of the United States
Section 3 - Scales and Symbols
Maps never show sizes and distances as they really are. They are always much
smaller than the part of Earth they represent. A short distance on a map stands
for a much greater distance on Earth.
The scale of a map shows the relationship between map distances and real
distances. A map’s scale can be
shown in many ways. The most
common is a line scale. The maps
on this page have two line
scales. One is for miles, and the
other is for kilometers.
Maps use symbols to show other
kinds of information. A symbol is
anything that stands for something else. Sometimes symbols look like what they
stand for. For example, mapmakers often use tiny airplane symbols to stand for
airports.
Color is another important map symbol. The color blue usually stands for
water. Mapmakers often use different colors to show separate states or countries.
Mapmakers use a map key to explain their symbols. (A key is also called a legend.)
The map key tells what each symbol stands for. Look at the maps on this
page. What does the star stand for?
Exploring Regions of the United States
Section 4 - Lines of Latitude
Suppose you want to describe the exact location of a place on Earth. To help you do
this, mapmakers invented a system of
imaginary lines around the globe. Some
of these lines run east and west around
the globe. They are called lines of
latitude. Lines of latitude are also
known as parallels because they are
always the same distance apart.
Lines of latitude tell us how far north
or south of the equator a place on Earth
is. The equator is a line of latitude. It
divides Earth into two halves. They are called the Northern Hemisphere and the
Southern Hemisphere. Because the United States lies north of the equator, it is in
the Northern Hemisphere.
The equator is the starting point for measuring latitude. It is labeled 0°, or zero
degrees. Parallels north of the equator are labeled N. The North Pole is
90°N. Parallels south of the equator are labeled S. The South Pole is 90°S. Lines of
latitude measure between 0° and 90°N or 90°S. The closer a parallel is to the
equator, the smaller its number of degrees. The closer it is to one of the poles, the
greater its number of degrees.
Section 5 - Lines of Longitude
Lines of longitude tell us how far to the east or west we need to go to locate a
place. Look at the map on this page. It shows lines circling Earth. They are called
lines of longitude. Lines of longitude are also called meridians.
Unlike lines of latitude, meridians are not
parallel to each other. All meridians meet
at the North Pole and the South Pole. The
distance between meridians is greatest at
the equator. That distance shrinks as you
move from the equator to the poles.
Can you find the line that is labeled prime
meridian on the map? This imaginary line
divides the world into the Eastern
Hemisphere and the Western
Hemisphere. Because the United States lies west of the prime meridian, it is in the
Western Hemisphere.
The longitude of the prime meridian is 0°. Lines of
longitude west of the prime meridian are labeled W.
Meridians east of the prime meridian are labeled E.
Lines of longitude measure between 0° and 180°.The
closer a meridian is to the prime meridian, the smaller its number of degrees. The
farther it is from the prime meridian, the greater its number of degrees.
Section 6 - The Global Grid
Mapmakers combine lines of latitude and longitude to form a grid. A grid is a set
of crisscrossing lines. The grid you see on the map below is
called a global grid because it covers all of Earth.
Using the lines of latitude and longitude on the global grid,
you can locate places anywhere in the world. For example,
suppose you want to locate New Orleans on the map below. It
is 30 degrees north of the equator, or 30°N. It is also 90 degrees west of the
prime meridian, or 90°W. When locating places on a map, latitude is stated first,
then longitude. So the location of
New Orleans is 30°N, 90°W.
The city of Uíge, Angola, is
located at 8°S, 15°E. To find this
location, put your finger on the
map where the equator and the
prime meridian meet. Move your
finger east to the 15°E meridian. So far, so good.
Now you have a problem. The 8°S parallel is not marked on this map. You know,
though, that 8°S must lie between the equator and 15°S. If you move your finger
along the 15°E meridian to the spot halfway between these two parallels, you will
find the city you are looking for.
Section 7 - Kinds of Maps
Geographers make different kinds of maps for different purposes. Maps that show
natural features are called physical maps. Physical maps show landforms, such as
mountains, valleys, and plains. Physical maps also show bodies of water, such as
rivers, lakes, and oceans. Other
maps show human features. For
example, a political map shows
cities, capitals, states, and
countries.
Special-purpose maps show just
one kind of information. Rainfall
maps, for example, show how
much rain falls in different parts of the world. Population maps show how many
people live in different areas. Language maps show what languages people speak in
different places.
The special-purpose map above is an elevation map of the United States. Elevation
is the height of the land above the ocean. The surface of the ocean, called sea
level, is at zero elevation. The highest point in North America is Mt. McKinley in
Alaska. Its elevation is 20,320 feet. What does the map show about your state’s
elevation?
Section 8 - The Northeast and Southeast
The maps on this page show the Northeast and Southeast regions of the United
States. These regions share a number of features. Both lie beside the Atlantic Ocean. A
low, flat plain runs along the coast in
both regions. It is known as a coastal
plain.
The Appalachian mountain range also
runs through both of these
regions. Large rivers flow out of these
mountains. The rivers that flow east
cut across the coastal plain to the
Atlantic Ocean. The rivers that flow
west drain into the Gulf of Mexico.
While they are alike in some ways, the
Northeast and Southeast regions have
different climates. The climate of a
place is the kind of weather it has
over time. It includes temperature,
rainfall, and wind conditions.
In the Northeast region, winters are
long and cold. Snowstorms are
common. Summers are warm and sometimes can be hot.
The Southeast region has a mild winter climate. Winters are usually warmer than in the
Northeast. Summers are hot and humid. Humid means damp or moist.
Section 9 - The Midwest and Southwest
The map on this page shows the Midwest and Southwest regions of the United States. These two
regions lie in the center of our country.
The Midwest is an inland region. It does not border any ocean. However, the Great Lakes form part
of the Midwest’s northern border. These
lakes are so large that they hold one-fifth
of all the fresh water on Earth.
Most of the Midwest is flat plains. The
Central Plains and Great Plains are covered
with some of the best soil on Earth. That
soil makes the Midwest an important farming
region.
The Mississippi River runs through the Central Plains.
It is the largest river in the United States. It is also
a busy water highway used by boats and barges.
Plains also cover the eastern part of the Southwest.
Farther west, the land rises to form the Colorado
Plateau. A plateau is a high, flat landform that rises
steeply from the land around it.
Most of the Colorado Plateau is fairly level. But it is crisscrossed by many deep canyons. The
largest and most famous is the Grand Canyon.
Section 10 - The West
Mountain ranges stretch across much of the West. The Rocky Mountains begin far
to the north, in Alaska. From
there they stretch south through
Canada, Montana, Idaho,
Wyoming, and Colorado.
The Great Basin lies to the west
of the Rockies. A basin is a bowlshaped landform that is lower
than the land around it. Small ranges of mountains circle around the Great Basin.
There are several mountain ranges along the Pacific coast. The Coast Ranges are
low hills that seem to rise right out of the Pacific Ocean. The Cascade Range and
the Sierra Nevada are further inland. (Sierra Nevada means “snowy range” in
Spanish.)
Between the Coast Range mountains and the inland mountains are two rich farming
valleys. One is California’s Central Valley. The other is Oregon’s Willamette Valley.
Hawaii is also mountainous. Volcanoes formed its islands long ago. A volcano is an
opening in Earth’s surface through which hot, melted rock and ash may pour out. As
the liquid rock cools, it forms a cone-shaped mountain.